This is a real simple way to color epoxy using leftover toner from a laser printer cartridge. This material would have gone to waste otherwise.
Step 1: What You Need
Toner - Can get it from a used copier or laser printer cartridge.
Cardboard - Makes cleanup easy, when done throw it out.
Gloves - Makes cleanup easier and keeps yours hands clean.
Epoxy - Any type or brand should work. I used Gorrila since it was cheaper at the store.
Mixing device - Anything could be used for mixing. Even a plastic knife. I like the Rockler Silicone Glue Brush since its reusable and once dry you can peel the epoxy off it.
Measuring spoon - You could also use a plastic spoon. I use a measuring spoon since its what I also use for measuring dyes.
Step 2: Prepare a Work Area
Toner can be quite messy and hard to clean out of carpeting and clothing. Make sure no fans are on that could blow it around. Also don't wear your good clothes when doing this.
Make sure to have everything laid out before starting. You dont want to get toner or epoxy on everything while you try to find an item you need.
Step 3: Coloring the Epoxy
Put some epoxy on the cardboard, before mixing the two parts of the epoxy add a small amount of toner. You don't need a lot. Now mix together using your mixing apparatus.
Step 4: Use the Colored Epoxy
Now use the colored epoxy. I used it to hide the rfid module in a coin I printed on my 3d printer. Coloring the epoxy helps hide the information about rfid type used.